Known methods and measurement systems for determining the alignment of the pulleys of a belt drive serve to determine or record the possible deviation from a desired target adjustment or target alignment of the pulleys with one another and/or in order to undertake corresponding corrections to the determined alignment of the pulleys against one another.
Known methods and measurement systems for determining the alignment of the pulleys to each other allow a precise determination of the orientation to the degree if the belt drive or the pulleys themselves satisfy certain boundary conditions. So it is necessary in the case of, known solutions in which a laser is placed against the pulley's running surface or lateral surface which extends circumferentially around the rotational axis of the first pulley, that a certain minimum distance between the laser and the receiver and also between the two pulleys is maintained, in particular, to achieve an acceptable level of measurement accuracy for the measurement or recording of a so-called horizontal angle displacement.
Such solutions are known, for example, in U.S. Pat. No. 6,704,115 B1, US 2003/0051354 A1, U.S. Pat. No. 6,098,297, U.S. Pat. No. 6,931,738 B2, U.S. Pat. No. 4,249,294 and DE 102 06 162 A1.
Known solutions in which the laser and the receiver are respectively placed flush against one of the two opposite disk surfaces of the respective pulley, only operate with sufficiently high measurement accuracy when the disk surfaces are very planar and level. Manufacturing technology-related deviations from a planar or a level structure of the pulley surfaces may, however, take on a magnitude that makes it impossible to work with such a laser and receiver due to high measurement inaccuracy. Solutions in which a laser and a receiver are positioned flush against the disk surfaces of the pulleys, for example, are known from DE 100 64 814 A1.
Underlying Task
The goal of the invention is to provide a method and a measuring system for determining the orientation of a first pulley of a belt drive in respect to a second pulley of a belt drive with which the alignment can be determined with great precision without the precision being restricted or severely limited as a consequence of the structure of the belt drive or the pulleys.
This goal is achieved according to the invention with a method with the features of Claim 1 and with a measurement system with the features of Claim 9.
The method according to the invention for determining the alignment of a first pulley of a belt drive in respect to a second pulley of a belt drive occurs by means of or by using a measurement system.
The measurement system comprises a laser light-emitting device and a laser light recording device.
The laser light-emitting device comprises a laser with a beam axis which is able to pivot around a laser pivot axis that is perpendicular to the beam axis of the laser. Furthermore, the laser is able to pivot around an adjustment axis of the laser light-emitting device that is perpendicular to the pivot axis of the laser.
The perpendicular orientation or perpendicular alignment of the laser pivot axis to the adjustment axis refers to the fact that the laser pivot axis may intersect with the adjustment axis but does not have to intersect with it, whereby, if the two axes do not intersect, these may form a common intersection point due to a translational displacement, and then may enclose a right angle. This applies not only with respect to these axes but subsequently to any axes when dealing with a perpendicular orientation or a perpendicular alignment.
The laser light recording device comprises a laser light sensor with a planar measuring field whereby the measuring field is a coordinate system having an X1 coordinate axis and a Y1 coordinate axis that is perpendicular to the X1 axis, whereby the laser light sensor is set up so as to record on the measuring field the X1 and Y1 coordinates of a laser light spot of the laser light beam that strikes the measuring field.
The laser light sensor can be any laser light sensor that is equipped with a level measuring field. A preferred embodiment is a laser light sensor which features several row sensors to form the measuring field. The X1 and Y1 coordinates recorded by the laser light sensor can be transmitted in the form of analogue or digital signals through a signal transmission path—also wirelessly—e.g. through an evaluation device, such as e.g. a computer, for example in the form of a laptop or a tablet, for further analysis. In particular, the laser light sensor may be a PSD sensor (PSD is an abbreviation for “Position Sensitive Device”).
The method comprises the following steps:
(A) locating a laser light-emitting device in an arbitrary position on the second pulley, whereby the laser light emitting device is located on the second pulley so that the laser pivot axis is parallel to the rotational axis of the first pulley or the second pulley.
(B) locating a laser light recording device in or at a position on the second pulley, which is at a distance from the position of the laser light emitting device, whereby the laser light recording device is located in such a way at the second pulley that the Y1 coordinate axis of the measuring field is parallel to the rotational axis of the second pulley, the X1 coordinate axis features a desired spatial orientation or spatial alignment, and the centre of the coordinate system features a predefined axial distance to the second pulley.
(C) alignment of the direction of the laser light beam emitted by the laser light emitting device at a right angle to the rotational axis of the second pulley by means of pivoting the laser around the adjustment axis, and recording the Y1 coordinate of the laser light spot on the measuring field by means of the laser light sensor upon irradiation of the measuring field with the aligned laser beam,
(D) location of the laser light recording device in or at least one position on the first pulley, whereby the laser light recording device is arranged in such a way on the first pulley that the Y1 coordinate axis of the measuring field is parallel to the rotational axis of the first pulley, the X1 coordinate axis shows a desired spatial orientation or spatial alignment and the centre of the coordinate systems shows a predefined axial distance from the first pulley.
(E) Irradiating of the measuring field with the aligned laser light beam of the laser from the laser light emitting device—with the laser light beam whose direction was aligned in accordance with Step C of the method—and recording of the X1 and Y1 coordinates of the laser light spots on the measuring field, whereby the measuring field is irradiated in at least one position by means of pivoting the laser around the laser pivot axis, so that the X1 and Y1 coordinates are recorded by at least three laser light spots on the measuring field, and
(F) Determination of the orientation of the first pulley in relation to the second pulley on the basis of the recorded X1 and Y1 coordinates of the laser light spots in at least one position and of the Y1 coordinates recorded in Step C.
Steps A and B are used to prepare step C of the method according to the invention, in which the direction of the laser light beam emitted by the laser of the laser light-emitting device is aligned by pivoting the laser around the adjustment axis at a right-angle to the rotational axis of the second pulley. In this way, a laser light reference plane can be created for the second pulley in the manner of a pivot plane by pivoting the laser around the laser pivot axis. Following the completed alignment, this pivot plane is then oriented at a right angle to the rotational axis of the second pulley and/or parallel to each of the two opposite disk surfaces of the second pulley.
For example, in order to create an arrangement in which the measuring field of the laser light recording device in Step C can be struck by the laser light beam, the laser of the laser light emitting device can be pivoted at a right angle to the beam axis of the laser's oriented laser pivot axis, whereby a desired or set pivot adjustment of the laser can preferably be locked around the laser pivot axis or is configured in a locked position. The lock here can be realized in any manner, e.g. in the form of a friction lock or a form lock.
As a result of the fact that in Step B, the laser light recording device is located in such a way on the second pulley that the Y1 coordinate axis of the measuring field is oriented parallel to the rotational axis of the second pulley, the X1 coordinate axis features a desired spatial orientation or alignment to the second pulley, and the centre of the coordinate system features a predefined axial distance from the second pulley, the spatial position of the coordinate system of the measuring field and/or the spatial position of the measuring field at or in the chosen position on the second pulley is defined exactly, and/or the spatial position of the measuring field relative to the second pulley is determined exactly since the position of the laser light recording device at the second pulley is specified or known. Accordingly, in step D as well, the definition of the coordinate system is carried out relative to the first pulley.
The desired spatial orientation or arrangement of the X1 coordinate axis can be realized in any conceivable way. In particular, a desired orientation of the X1 coordinate axis or a desired arrangement of the X1 coordinate axis relative to the first and/or second pulleys and/or relative to the rotational axis of the first and/or second pulley, such as by pivoting around the pivot axis of the laser light recording device, can be set in such a way that the pivot axis is oriented parallel to the Y1 coordinate axis of the measuring field. Preferably, the measuring field can be locked in the pivot position chosen for creating the desired alignment of the X1 coordinate axis.
Using the Y1 coordinates of the laser light spot that was recorded on the measuring field in Step C by the laser light sensor by irradiating the measuring field with the aligned laser light beam—the laser light beam which is orientated or arranged at a the axial distance of the laser light beam or the laser light reference plane from the second pulley can also be determined arranged in such a position on the second pulley that the Y coordinate axis of the measuring field is oriented parallel to the rotational axis of the second pulley, and the centre of the coordinate system shows a predefined axial distance to the second pulley. As a result it is possible, by using the Y-coordinate of the laser light spot as determined in Step C and the pre-defined axial distance, to determine or calculate, the distance of the laser light beam or the laser light reference plane to the second pulley.
After the preparatory steps A through C, steps D and E are intended to actually record the relative orientation of the two pulleys to one another. For this purpose, in Step D, the laser light recording device—after it has been removed from the second pulley—is arranged in at least one position in the already described manner to the first pulley, whereby preferably a predefined axial distance to the first pulley can be chosen which corresponds to the predefined axial distance to the second pulley as per Step B. Maintaining the predefined or specified distance can be achieved, in particular, by providing a spacer at the laser light recording device which allows a predefined or predetermined axial distance to be maintained in such a way that the spacer ensures, when arranging the laser light recording device in the position on the second pulley or at least in one position at the first pulley, that this predefined axial distance is maintained. Preferably, a predefined axial distance from the first pulley should be chosen which corresponds to the predefined axial distance to the second pulley as per Step B, which provides the advantage, among others, that this reduces the work involved in determining the alignment of the first pulley relative to the second pulley. Furthermore, it is advantageous to not undertake any re-adjustments that may lead to errors.
In step E, the irradiation of the measuring field is performed with the laser light or the laser light beam of the laser of the laser light-emitting device whose direction has been aligned as per Step C, and the recording of the X1 and Y1 coordinates of the light spots that are forming on the measuring field, whereby the measuring field can be irradiated in at least one position by pivoting the laser around the laser pivoting axis in such a way that the X1 and Y1 coordinates of at least three laser light spots can be recorded on the measuring field. During the irradiation of the measuring field with the laser light or the laser light beam of the laser of the laser light emitting device, the laser light emitting device remains in its position on the second pulley and the alignment of the direction of the laser light beam made in Step C is maintained. The only movement that is made is the pivoting of the laser around the laser pivot axis in order to irradiate the measuring field with the laser light beam aligned in Step C, while maintaining the position of the laser light emitting device on the second pulley and while maintaining the set orientation of the laser beam.
Because the X1 and Y1 coordinates are recorded by at least three laser light spots on the measuring field, the position of the above-described laser light reference plane relative to the first pulley can be determined with precision since a plane is clearly defined by three points, and the X1 and Y1 coordinates of these laser light spots are coordinates of at least one coordinate system that is located in a known position relative to the first pulley, because the position in which the laser light recording device is located in step D on the first pulley is known or specified and/or because the actual position is a pre-defined or specified position. In the event that in step D, for example, an arrangement of the laser light recording device is planned in two or three different positions at the first pulley, there would be two or three coordinate systems with a known position in relation to the first pulley.
It is understood that the X1 and Y1 coordinates of the laser light spots can be transformed by coordinate transformation to a single coordinate system which has its origin in a defined position in relation to the first pulley so that the position of the laser light reference plane can be beneficially presented in a simple way in one single coordinate system.
From the position of the above-described laser light reference plane relative to the first pulley, one can then also determine the orientation of the first pulley with respect to the second pulley by including or using the distance of the laser light reference plane to the first pulley (see also above), whereby the alignment comprises the position of the laser light reference plane relative to the first pulley and the distance of the laser light reference plane to the second pulley and/or which is characterized by the position of the laser light reference plane relative to the first pulley and the distance of the laser light reference plane to the second pulley.
In light of the above, the method includes Step F for determining the alignment of the first pulley with respect to the second pulley on the basis of the recorded X1 and Y1 coordinates of the laser light spots in at least one position and the Y1 coordinate recorded in step C, whereby the recorded X1 and Y1 coordinates of the laser light spots are the X1 and Y1 coordinates recorded in Step E.
Somewhat more detailed or alternatively, the method can also include the following Step F: Determining the alignment of the first pulley with respect to the second pulley on the basis of the recorded X1 and Y1 coordinates of the laser light spots and the position of the measuring field's coordinate system (or the location of the origin of the measuring field's coordinate system) relative to the first pulley in at least one position or in at least one predetermined position on the first pulley and on the basis of the Y1 coordinate determined in Step C. Thus one can determine the position of the measuring field's coordinate system relative to the first pulley in at least one position of the laser light recording device at the first pulley from the coordinates of this position in a pulley coordinate system of the first pulley, which has a predefined position or specified position in relation to the first pulley, or which has a coordinate system that is fixed to the first pulley. In order to define the position of the laser light recording device on the pulley, one could, for example, use an arbitrary body point on the laser light recording device, whose coordinates in the pulley coordinate system define the position of the laser light recording device.
Accordingly, the respective position of the laser light emitting device may be defined at the respective pulley. In particular, one can very simplistically use the coordinates of the centre of the measuring field's coordinate system in the pulley coordinate system to define the position of the laser light recording device on the pulley.
Altogether, using the above-described methods, one can then determine the alignment of the first pulley in relation to the second pulley with high precision, without significantly limiting the precision due to the design of the belt drive or the pulleys. In particular, because of the fact that in Step C the direction of the laser light beam is aligned at a right angle to the rotational axis of the second pulley, manufacturing-related deviations from a planar or level design of the disk surfaces are irrelevant—completely in contrast to current solutions in which a laser and a receiver are placed flush against the disk surfaces of the pulleys. The alignment of the direction of the laser light beam at a right angle to the rotational axis of the second pulley can be realized in any conceivable manner. So it would be possible, for example, to align the laser light beam at a right angle to a stop rod in the form of a round rod or a rod in the form of a circular cylinder, with its lateral surface being placed flush against the side surface or the continuous running surface of the pulley in order to provide a parallel orientation to the rotational axis. As a result of this, one would beneficially no longer be dependent on one of the two opposing disk surfaces, which may deviate quite strongly from an ideal planar design. Above all, due to the available alignment functionality of the laser, this method can be used very flexibly for very different belt drives.
It is particularly preferable that the laser of the laser light-emitting device is a point laser. Using a point laser, the method can in particular also be used, due to the beam quality of the point laser, for the alignment of pulleys which have a large distance of, for example 10 meters or more than 10 meters or more than 20 meters, whereby in most belt drives the distances between pulleys are well under 10 meters—most often below 1 meter, so that a very precise determination of the alignment can be made using a point laser.
It is particularly preferable that the laser or point laser may have a beam deviation of less than 0.3 mrad, combined with high focusability.
The arrangement of the laser light recording device in at least one position on the first pulley or in the position on the second pulley can preferably be done using a holding device for the laser light recording device, which is designed in such a way that the laser light recording device is held in an operationally secure position on the first or second pulley. Also, the laser light emitting device may preferably have such a holding device.
Steps A and B of the method may occur concurrently or at least partially at the same time. Steps A and B can be performed sequentially or in reverse order, in such a way that Step B cannot only be done after Step A, but also that Step A can be undertaken after Step B. Steps C, D and E are all carried out after Steps A and B, whereby Step D is done after Step C, and Step E after Step B. Step F is preferably carried out after step E, however, it can also be completed during Step E, in particular if a computer is used to determine the alignment at least at times during Step E.
An axial distance in front and behind is to be understood as a distance in the axial direction, whereby the axial orientation is a parallel direction to the rotational axis of the first or second pulley.
The X1 and Y1 coordinates described above and below or the X2 and Y2 coordinates of the laser light spot of the laser light beam striking the measuring field, or of the laser light spots that form on the measuring field during irradiation with the laser light beam, are, of course, the coordinates of a point, even though the laser light spot always has two-dimensional dimensions on the measuring field. The X1 and Y1 coordinates or X2 and Y2 coordinates of the laser light spot are always to be understood above and below as the coordinates of a point that can be determined from the structure of the surface and/or the light distribution of the laser light spot on the surface. In particular, this point may be, for example, the centroid of the laser light spot. The determination or calculation of the point can preferably be automated by means of a calculation device, such as a computer, on the basis of the digital and/or analogue signals attributed to the respective laser light spot, which are emitted by the laser light sensor. If the laser light sensor is a PSD sensor, the calculation of the centroid can be done, for example, in a known way on the basis of suitable resistance measurements at the sensor corners or the field corners. In calculating the centroid, a surface is analyzed on the respective measuring field. This calculation in a PSD sensor can make it possible to determine movements of a laser light spot on the measuring field in the micron range, so that the size of the laser light spot plays a minor role in a PSD sensor. In a preferred embodiment of the method according to the invention, the laser light sensor is able to pivot around a pivot axis which has a parallel orientation to the Y1 coordinate axis of the measuring field, whereby the laser light recording device or the laser light sensor in Step D is arranged in three positions separate from one another on the first pulley, and in each position the laser and the laser light sensor are brought into a relative position to one another by pivoting the laser light sensor around the pivot axis, and/or by pivoting the laser around the laser pivot axis so that the laser light beam can strike the measuring field; whereby in each position, the X1 and Y1 coordinates of at least one laser light spot are recorded on the measuring field.
With this preferred embodiment, the laser light recording device is to be attached on the first pulley in three positions that are at a distance from one another, so that in a simple and practical manner, one can record the X and Y coordinates of altogether at least three laser light spots on the measuring field by moving the laser light recording device to the second pulley, these laser light spots are needed to determine the position of the aforementioned laser light reference plane relative to the first pulley. A preferable embodiment here is a pivoting position of the laser light sensor around the rotational axis which can be locked, as well as a pivoting adjustment of the laser around the laser pivot axis which can be locked, so that preferably the measuring field can be irradiated with the laser light beam while the relative position of the laser to the laser light sensor is maintained in an operationally secure fashion.
Preferably, the three positions are located at a distance from one another in the circumferential direction or in the circumferential direction around the rotational axis of the first pulley and/or the three positions are chosen such that the centre of the coordinate system of the measuring field is located in one of the positions at a distance from the centre of the measuring field in each of the other remaining positions in circumferential direction or in circumferential direction around the rotational axis of the first pulley. Such positions may be beneficially attained in particular by providing suitable retaining devices or holding devices for holding or attaching the laser light recording device at the first pulley with high accuracy and reproducibility.
For an especially beneficial embodiment of the invention, two of the positions are chosen in such a way that a straight connecting line connecting the centre of the coordinate system of the measuring field in the one position with the centre of the coordinate system of the measuring field in the other position, intersects the rotational axis of the first pulley. By providing this geometry, a large distance can be achieved between the two positions, so that ultimately the accuracy of the alignment to be determined in respect of the first pulley can beneficially be increased in reference to the second pulley. The greater the chosen distance is between the respective positions, the smaller is the influence of possible error sources or influencing factors which can limit measurement accuracy, such as, for example, the measurement accuracy of the measuring field.
In a further advantageous embodiment of the method, the centre of the coordinate system is at a distance from the rotational axis in each of the two positions, which corresponds to the diameter of the pulley or 0.8 to 0.95 times the diameter of the pulley. With such a large distance, the alignment of the first pulley with respect to the second pulley can be determined very accurately because the sources of error or influencing factors only have a slight influence. In particular, when using comparably small pulleys with a diameter of less than 80 mm, a distance within the above ranges can be particularly well implemented and is therefore advantageous.
In a practical embodiment of the method, the laser light recording device is located in step D in a position on the first pulley, and the laser of the laser light emitting device is pivoted in Step E in such a way that the laser light spot moves on the measuring field.
Also by using this practical embodiment of the method, the alignment of the first pulley with respect to a second pulley can be very accurately determined, whereby preferably the laser light recording device is to be arranged only in a position on the first pulley, and the minimum of three laser lights spots which are necessary to determine alignment can be formed by simple movement of the laser light spots on the measuring field, whereby this movement of the laser light spot can be created through simple pivoting of the laser around the laser pivot axis.
In a further preferred embodiment, the laser light recording device features a second measuring field with a coordinate system having an X2 coordinate axis and a Y2 coordinate axis which is at a right angle to the X2 coordinate axis, whereby the Y2 coordinate axis of the second measuring field is parallel to the Y1 coordinate axis of the first measuring field, whereby furthermore a beam splitter is provided which splits the laser light beam of the laser light emitting device prior to striking the measuring fields into a first partial beam and a second partial beam, whereby the first partial beam may strike the first measuring field, and whereby the second partial beam may strike the second measuring field, whereby the travel time of the first partial beam to the first measuring field is less than the travel time of the second partial beam to the second measuring field, whereby the beam splitter has a level entry surface and a parallel exit surface, whereby the entry surface is aligned parallel to the Y1 coordinate axis, whereby the first and second measuring field are aligned with respect to the beam splitter in such a manner that when the first partial beam creates a laser light spot in the centre of the coordinate system when irradiating the first measuring field at a right angle to the Y1 coordinate axis, the second partial beam creates a laser light spot in the centre of the coordinate system of the second measuring field when irradiating the second measuring field, whereby as a consequence of the difference in travel time between the two partial beams in a state in which the beam direction of the laser light beam in Step C deviates from the state and or the situation, in which the beam direction is at a right angle to the rotational axis of the second pulley, a difference (or a difference which is not zero) between the Y1 coordinate of the laser light spot on the first measuring field and the Y2 coordinate of the laser light spot on the second measuring field is present, so that in Step C, the laser is pivoted around the adjustment axis until the difference between the Y1 and Y2 coordinates equals zero, or is substantially equal to zero.
This preferred embodiment advantageously facilitates very simple and practical alignment of the direction of the laser light beam of the laser light emitting device at a right angle to the rotational axis of the second pulley in Step C. The laser is only to be rotated around the adjustment axis until the difference between the Y1 and Y2 coordinates is equal to zero or the Y2 coordinate is no longer different than the Y1 coordinate.
The first partial beam is preferably the partial beam that extends continuously through the beam splitter which emerges from the level exit surface or which emerges from the level exit surface in an offset position parallel to the laser light beam while the second partial beam can be the partial beam that is reflected at the two-dimensional entry surface. The reverse constellation is also conceivable, which means that the first partial beam is the reflected partial beam and the second partial beam is the partial beam emerging from the exit surface. In particular, for example, one can also provide at least one further deflection device, such as a mirror, in order to make it possible for the first partial beam to strike the first measuring field and the second partial beam to strike the second measuring field. Furthermore, one can provide, for example, at least one lens to influence or shape the beam path of the partial beams.
The measurement system for determining the alignment of a first pulley of a belt drive with respect to a second pulley of the belt drive comprises a laser light emitting device and a laser light recording device, whereby the laser light emitting device comprises a laser with a beam axis which can be pivoted around a laser pivoting axis that is oriented at a right angle to the beam axis of the laser, whereby the laser is further pivotable around an adjustment axis of the laser light emitting device which is at a right angle to the laser pivot axis of the laser light emitting device, whereby the laser light recording device includes a laser light sensor with a level measuring field, whereby the measuring field has a coordinate system with an X1 coordinate axis and a Y1 coordinate axis perpendicular to the X1 coordinate axis, whereby the laser light sensor is set up to record the X1 and Y1 coordinates of a laser light spot of the laser light beam on the measuring field which strikes the measuring field.
The laser light emitting device is set up to be arranged in a position on a pulley such that the laser pivot axis is oriented parallel to the rotational axis of the pulley. The laser light recording device is oriented in such a way that it can be arranged in a position on a pulley such that the Y1 coordinate axis of the measuring field is oriented parallel to the rotational axis of the pulley, the X axis features a desired spatial arrangement or orientation, and the centre of the coordinate system has a predefined axial distance to the pulley. This alignment of the laser light emitting device and laser light recording device can, for example, be realized by means of a holding device or a retention device of the laser light emitting device or the laser light recording device, for holding or alignment in the respective position on the pulley.
Using the measurement system—it is possible, on the basis of the aforementioned reasons—to determine the alignment of a first pulley of a belt drive in relation to a second pulley of the belt drive with high accuracy without limiting or significantly limiting the accuracy due to the design of the belt drive or the pulleys.
In a practical embodiment of the measuring system, the laser light recording device has a second measuring field with a coordinate system with an X2 coordinate axis and a Y2 coordinate axis which is at a right angle to the X2 coordinate axis, whereby the Y2 coordinate axis of the second measuring field is parallel to the Y1 coordinate axis of the other measuring field, whereby furthermore a beam splitter is provided which splits the laser light or the laser light beam of the laser light emitting device prior to striking the measuring field into a first and a second partial beam, whereby the first partial beam may strike the first measuring field, and the second partial beam may strike the second measuring field, whereby the travel time of the first partial beam to the first measuring field is lower than the travel time of the second partial beam to the second measuring field, whereby the beam splitter has a level entry surface and a parallel exit surface, whereby the entry surface is oriented parallel to the Y1 coordinate axis, whereby the first and second measuring field are oriented in such a way in relation to the beam splitter, that when the first partial beam forms a laser light spot upon irradiation of the first measuring field at a right angle to the Y1 coordinate axis in the centre of the coordinate system of the first measuring field, the second partial beam forms a laser light spot in the centre of the coordinate system of the second measuring field upon irradiation of the second measuring field.
This practical embodiment advantageously allows, in a very simple and practical manner, the alignment of the direction of the laser light beam emitted by the laser light-emitting device at a right angle to the rotational axis of the second pulley. The laser is only to be pivoted around the adjustment axis until the difference between the Y1 coordinate and the Y2 coordinate is equal to zero.
In a preferred embodiment of the measuring system, the laser light emitting device has at least one round rod for flush placement against the lateral surface or cylinder surface of the round rod to at least one continuous surface of the pulley when aligning it in the position of the pulley, whereby the circumferential surface of the pulley extends in the axial direction of the pulley and around a rotational axis, and whereby the longitudinal axis of the round rod is aligned parallel to the laser pivot axis of the laser light emitting device. Using such a round rod or a circular cylindrical rod, the laser light emitting device can be aligned in such a position on the pulley that one can implement a very exact parallel orientation of the laser pivot axis to the rotational axis, which results in a very high degree of precision of the determined alignment of the pulleys. The circumferential surface against which the lateral surface is placed flush can be the running surface or the side surface of the pulley or a partial surface of this. These surfaces are as a rule manufactured much more precisely that any of the two mutually opposite surfaces of the pulley so that alignment by means of these surfaces can be achieved with a great deal of precision when determining the alignment of the pulleys towards one another.
In a further preferred embodiment of the measuring system, the laser light recording device comprises at least one rod for flush placement of the lateral surface or cylindrical surface of the round rod against at least one circumferential surface of the pulley when attaching the same in the position on the pulley, whereby the circumferential surface of the pulley extends in an axial orientation of the pulley and circumferentially around the rotational axis, and whereby the longitudinal axis of the round rod is aligned parallel to the Y coordinate axis of the measuring field.
Using such a round rod or a circular-cylindrical rod, the laser light recording device can be arranged similar to the aforementioned information in a position on the pulley so that a very exact parallel alignment of the Y1 coordinate axis of the measuring field to the rotational axis can be realized, along with providing high accuracy in determining the alignment of the pulleys to one another. In particular, by means of such a round rod, the pivot axis of the laser sensor can advantageously be positioned very close to the edge area of the respective pulley, which beneficially allows for large measurement distances between various positions to be realized which advantageously improves the accuracy of the determined alignment.